rickettsia

noun rick·ett·sia \ri-ˈket-sē-ə\

plural rick·ett·si·as or rick·ett·si·ae\-sē-ˌē, -ˌī\ also rick·ett·sia

Definition of RICKETTSIA

: any of a family (Rickettsiaceae) of rod-shaped, coccoid, or diplococcus-shaped, often pleomorphic gram-negative bacteria that are intracellular parasites of arthropods (as lice or ticks) and when transmitted to humans cause various diseases (as typhus)

— rick·ett·si·al \-sē-əl\ adjective

See rickettsia defined for kids

Origin of RICKETTSIA

New Latin, genus name, from Howard T. Ricketts †1910 American pathologist

First Known Use: 1919

Medical Dictionary

rickettsia

noun rick·ett·sia \ri-ˈket-sē-ə\

Medical Definition of RICKETTSIA

capitalized : the type genus of the family Rickettsiaceae comprising rod-shaped, coccoid, or diplococcus-shaped often pleomorphic bacteria that live intracellularly in biting arthropods (as lice or ticks) and when transmitted to humans by the bite of an arthropod host cause a number of serious diseases (as Rocky Mountain spotted fever and typhus)

plural rick·ett·si·ae \-ˌē\ also rick·ett·sias or rick·ett·sia : any bacterium of the order Rickettsiales and especially of the family Rickettsiaceae